Development of a granular cohesive model for Rolling Contact Fatigue analysis: influence of numerical parameters

In Rolling Contact Fatigue (RCF), understanding initiation and propagation failure mechanisms remains a challenge. A cohesive Finite Element model has been developed to investigate microstructure role on initiation mechanisms. The approach consists in modelling the Grain Boundary (GB) progressive damage (from initial undamaged state to failure). In this paper, numerical singularities at triple junctions are highlighted and cohesive stiffness values (for undamaged and fully damaged GB) are defined. Preliminary results underscore the influence of damage application: a linear relation between cohesive stiffness and damage is not suitable to simulate progressive damage.